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Everything posted by Ender
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Ok, maybe I understand what you're saying. But, let me know if I'm wrong, couldn't it be that the spaceship is just accelerating away from the horizon with an acceleration equal to the one that's pulling it in (since you're not in the black hole you should be able to do that)? And in that case it's like if you were still and when you let go of the person, he will be pulled inside starting from almost stil.. Does that make sense? I don't think I understood what you said. You are saying that the horizon is moving at the velocity c? And the infalling observer would experience lenght contraction at the horizon? But I've always read that due to GR the horizon must be a place like everywhere else in the Universe right? So I thought it would be nothing fancy, passing through the horizon..
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Ok thank you. But when the infalling object is, for example, a person, he cannot reach the speed of light. And also, maybe there's a spaceship bringing him right near the Schwarzschild radius and giving him an initial speed that's almost zero, how can he reach the speed of light when at the Schwarzschild radius?
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Ok but what is rs? Is it a distance? Because if it is, the formula doesn't give the dimension of a speed.. Thank you for the response by the way
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I was thinking about escape velocities and I ended up thinking about black holes and what would happen if someone or something fell into one. In particular, I asked myself: if something was to start still at the event horizon and then, drawn by the gravitational force, was start "falling" toward the center, at what speed would it reach the singularity? Does it even make sense to ask a question like that? I have some calculus that may make no sense, but I wanted to show it to you to know what you thought: Probably you all know how to calculate the escape velocity: E® is the initial kinetic and gravitational potential energy, on the surface of the planet E(infinity) is the energy when you reach an infinite distance from the planet E®=1/2*m*v^2-G*M*m/r E(infinity)=0 From E®=E(infinity) you find v. But what if you thought about it in another way? E®=mgr E(0)=1/2*m*v^2 In this case it's like if you are starting from the surface of the planet and you're falling at the center of it.. Does that make sense? If you use this last formula to find the escape velocity from Earth you'll find that it's the same (because g=G*M/r^2) but this time you're falling in, not out, so it's the velocity you have when you arrive at the center. Now let's apply it to black holes: on the event horizon the escape velocity is c.. does that mean that if you start on the event horizon and fall down the black hole, when you arrive at the singularity your velocity is c? Thank you very much for your time. I'm sorry, all the ( r ) became ®
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I'm not sure if I believe that our Universe came from a superior intelligence of some sort.. but I'm almost sure we don't have any evidence about anything that came before the Big Bang. We don't even know if the laws of our Universe apply where there is no time and space! It's far more difficult than thinking outside the box.
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I've read Hawking's "solution" to the firewall paradox but many scientists are not really convinced (me neither): (I'm sorry I don't know how to put the quote thing, hope this is fine) "It is not clear what he expects the infalling observer to see," says Polchinski. "It almost sounds like he is replacing the firewall with a chaos-wall, which could be the same thing." Samuel Braunstein of the University of York, UK, who has waded into the the firewall debate previously, also isn't convinced: "I don't see any evidence which really demonstrates that the thing he is talking about doesn't have a firewall." found: http://www.newscientist.com/article/dn24937-stephen-hawkings-new-theory-offers-black-hole-escape.html#.UvUCLvRDvwh We don't even know what happens at the singularity, maybe information is preserved in some way that still needs to be found, and there will be no firewall. And I also have a question: are we sure that Hawking radiation exists? Has there been a real and undoubted proof? Or is it only a mathematical assumption? Because on Wikipedia under "experimental observation of Hawking radiation" I just found: Under experimentally achievable conditions for gravitational systems this effect is too small to be observed directly. In September 2010, however, an experimental set-up created a laboratory "white hole event horizon" that the experimenters claimed was shown to radiate Hawking radiation,[23] although its status as a genuine confirmation remains in doubt. from: http://en.wikipedia.org/wiki/Hawking_radiation#Experimental_observation_of_Hawking_radiation
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Hello GustavRichter, I'm not a super expert in QM (even though I'm studying to get there) but I've read a lot about this Orch-Or theory and I've really been fascinated by it. I think the theory is not very famous and it's just making its way through the science community, just because it "mixes" QM with consciousness and the self. It may be deemed to be a bit new age, trying to give an explanation of how this strange phenomenon of awareness was born. Personally, I don't see the theory as a new age thing. I just wanna see things in a clear way and if this means breaking the mainstream view which, sometimes, doesn't even address the problem of consciousness directly, I'm happy to do so. I think it's a hard question for a quantum physicist, to give a personal opinion about the theory. That's because it does not only involve QM, but also that complex piece of flesh that we have in our cranium. It does not only involve quantum entanglement and the problem of decoherence and superposition, but also the structure of the microtubules and the "environment" in which the orchestrated objective reduction must take place, the brain. That's the reason why Sir. Penrose is a mathematician/physicist and Dr. Hameroff is an anesthesiologist and is more competent in the studies of the brain structure and functions. My personal opinion is that I wouldn't just put aside the theory, only because it's a bit non-mainstream, you know. It still hasn't been attacked in such a way to say "It has more evidence against it than in its favour" and it's, probably, one of the few candidates right now. I mean, if QM rule the universe, why shouldn't it rule our brain and mind too? (if we find the real evidence of some sort of collapse of this brain function). There's been this experiment (maybe you've heard of it, if not I recommend you check it out) called the "double slit experiment" which showed, simply put, that a particle behaves as a wave if you don't make a measurement on it. That means that a single particle exists in different states and interferes with itself until you measure it, until you have certain information about its position. What does it mean? Some have come to the conclusion that consciousness has to be involved in some kind of way (even though it's not very clear, at least to me, whether a conscious observer is needed in order to make reality behave in a certain way or not) or maybe that this could be the key to understanding it. The point is, that QM is probably the weirdest thing that scientists have found since the origins of the studies and it is still not completely understood. On the other hand, consciousness also has a great reputation for being mysterious, because it is something subjective and not easy (at all) to measure in an objective, absolute way. Let's put the two together and see what comes out (why not?).. I've read that the theory also involves quantum gravity, which makes everything a bit more difficult, since we don't really have a theory for quantum gravity.. It's still an open study I guess. I like the theory because it's new and quite original, but I cannot say that I'm completely convinced until, we find striking evidence for it. Right now, it's all about if you think of consciousness as some secondary not-really-important event, or as a fundamental matter (as it is in the theory, because it also revolutionizes the nature of reality at a fundamental level). Hope mine wasn't only blathering and that it was of some kind of help.